Edge lock for metal panels



Dec. 26, 1967 F, A. JACKSQN 3,359,699

EDGE LOOK FOR METAL PANELS Filed May 26, 1965 ATTORNEY United StatesPatent 3,359,699 EDGE LOCK FOR METAL PANELS Frank A. Jackson, Kokomo,Ind., assignor to Pittsburgh Plate Glass Company, Pittsburgh, Pa., acorporation of Pennsylvania Filed May 26, 1965, Ser. No. 458,933 2Claims. (Cl. 52619) ABSTRACT OF THE DISCLOSURE A flush metal doorassembly having unitary panel framing members joined into a frame, rigidcore material filling the space within the frame, a pair of panelsdisposed on opposite sides of the frame and adhesively secured to thecore material to thereby hold the door components in assembled relation,and an integral T- shaped flange on each panel framing member to providelongitudinally extending, opposed grooves that closely receive andsecurely lock the edges of the panels along the edge surfaces of thecomplete-d door assembly.

This invention relates to metal panel assemblies and, in particular, tometal panel assemblies that have a thin metallic face panel or skincovering a structural grid of panel framing members.

More specifically, this invention involves a novel panel framing memberfor use in the construction of prefabricated metal panels, such as flushmetal doors or the like. The panel framing member of this invention hasintegrally formed thereon a unique skin or panel edge locking structurethat securely retains and completely conceals the edges of the metallicskin along the edges of the composite panel assembly.

It is an object of this invention to provide an improved flush metaldoor construction that will successfully withstand twisting forceswithout resulting in the edges of the metal skin becoming loose andmoving away from the door framework perpendicularly to the door edge.

Another object of this invention is to provide a durable and economicalmetal panel assembly wherein the relatively expensive and appearancemarring mechanical expedients of welding, drilling, tapping, rivetingand the like are eliminated.

A further object of this invention is to provide an attractive andsturdy metal panel assembly wherein the edges of its metallic skin arecompletely concealed along the edges of the panel assembly.

A still further object of this invention is to provide an improved andinexpensive panel framing member that gives rigid structural support toa panel face member while securely retaining and completely concealingthe edges of the panel.

Summary of the invention The panel assembly of this invention hasparticular application for use in connection with the construction offlush metal doors. In accordance with this invention, there is provideda laminated flush metal door assembly with smooth, seamless surfacescomprising a rectangular frame of unitary panel framing members, rigidcore material filling the space within the frame, a pair of panelsdisposed on opposite sides of the frame and adhesively secured to thecore material to thereby hold the door components in assembled relation,and an integral T- shaped flange on each panel framing member to providelongitudinally extending, opposed grooves that closely receive andsecurely lock the edges of the panels along the edge surfaces of thecompleted door assembly.

These and other objects, features and advantages of 3,359,699 PatentedDec. 26, 1967 the present invention will be better understood whenreference is had to the accompanying drawings wherein similar parts areusually designated by the same numeral and in which:

FIG. 1 is a perspective view of a prefabricated flush metal doorconstructed in accordance with this invention and in which various partsof the door have been partly broken away to better illustrate itsconstruction;

FIG. 2 is a cross-sectional view taken along the line II--II of FIG. 1and shows one preferred embodiment of the panel framing member of thisinvention; and

FIG. 3 is a cross-sectional view taken through an alter nate preferredembodiment of the panel framing member of this invention.

The metal panel assembly shown in FIG. 1 and constructed in accordancewith the teachings of the present invention is a prefabricated flushmetal door. As illustrate-d, the door 10 has a rigid frame or grid ofpanel framing members having identical cross-sections and comprisingvertical stiles 12 and 14 and top and bottom rails 16 and 18. Thesepanel framing members are preferably mitered and welded together attheir extremities. Additional rigidity and/or support for hardware maybe provided by means of suitable bracing members, such as those shown at20, 22 and 24.

The door 10 is provided with front and back panel sheets or skins 26 and28 and an insulating core material 30, such as rigid polyurethane foam.A suitable adhesive material 32, such as an epoxy resin or nitrilerubber adhesive, is disposed between the panel skins 26 and 28 and theinsulating core material 30 to securely bond the panel assemblytogether.

The panel sheets or skins 26 and 28 are of essentially uniform thicknessthroughout and have substantially right angled edge flanges 27 along thefour marginal edge portions of the sheets. The edge flanges 27 arepreferably formed by a bending operation, such as brake forming.

As aforesaid, panel framing members 12, 14, 16 and 18 have identicalcross-sections. Thus, when reference is made herein to specific detailsof the structure of one such panel framing members, it is to beunderstood that the same details apply equally well to the other panelframing members of the metal panel assembly.

The panel framing members 12, 14, 16 and 18, two of which are shown inFIG. 2, comprise relatively heavy metal shapes, preferably aluminum ormetal alloy extrusions. These framing members comprise a generallychannel-shape body portion having a web 34 and a pair of flanges 36 and38. An integral T-shaped metal flange 40 extends longitudinally andoutwardly of the channel web 34 to provide therebetween a pair oflongitudinally extending opposed grooves 42 and 44 of substantiallyuniform width throughout their depth.

The width of the grooves 42 and 44 is dimensioned to be approximatelythe same as the thickness of the panel sheets or skins 26 and 28. Thegrooves 42 and 44 open or face outwardly towards opposite sides of thepanel framing member and the T-shaped flange 40 and grooves 42 and 44,as shown in FIG. 2, are spaced substantially back from the flanges 36and 38 such that they are, in effect, located along the centrallongitudinal portion of the edge of the door frame and the finallyassembled door.

The panel framing member shown in FIG. 3 has a similar cross-section tothose shown in FIG. 2, except that a portion 46, intermediate theextremities of the channel web 34, is recessed inwardly of the adjacentextremities of the channel flanges 36 and 38. This structural variationhas been found to be useful where it is desired to place the panel edgeflanges in slight tension. Placing the panel edge flanges in slighttension within the grooves 42 and 44 will assist in preventing the paneledges from being released from these grooves when the panel assembly issubjected to severe use.

The illustrated metal panel assembly or door is assembled by firstcutting and welding framing members 12, 14, 16 and 18 to shape andthereafter providing additional rigidity and/ or support for hardware bymeans of welding thereto suitable bracing members, such as thoseidentified at 29, 22 and 24. The previously welded grid of panel framingmembers is then filled with a rigid insulating core material 30 and asuitable adhesive 32 is applied directly to the core material. The frontand back skins 26 and 28 are then applied to the respective sides of thedoor frame, and the edge flanges 27, around the entire marginal edgeportions of the skins, are inserted into the grooves 42 and 44 of thegrid of panel framing members. The entire panel assembly is then runthrough pressure rolls to laminate or positively bond the skins to thecore material and to insure smooth flat surfaces.

As shown in FIGS. 2 and 3, the grooves 42 and 44 are dimensioned to beapproximately the same thickness as the flanges 27, thereby providing arelatively close fit therebetween, so that the flanges 27 may be readilypositioned in the grooves for the rolling operation. Thus, when theskins are laminated to the door core material 30 during the rollingoperation, the bent or rolled-over edge flanges 27 of the skins arereceived into grooves 42 and 44 to substantially the full depth of thesegrooves. After lamination, the longitudinally extending T-shaped flangeportion of the panel framing members conceals the marginal edge of eachof the skins along the edge of the panel assembly and, in addition,locks the edge flanges against movement perpendicular to the panelframing members.

It is to be noted that the completed metal door of this invention isconstructed to successfully withstand twisting forces without resultingin the edges of the metal skins becoming loose and moving away from thedoor framework perpendicularly to the door edge. Furthermore, it will benoted that the exterior of the door is completely flush with all exposedsurfaces lying in a continuous un broken plane. Slam tests conducted onthis door prove that it will withstand more than two million cycles withno change in its sturdy grid construction or smooth, seamless laminatedsurface. This is equal to more than twenty years of actual operation.

It will be clear to those skilled in the art that the structure asherein disclosed is comparatively inexpensive to manufacture andeliminates the apperance marring mechanical expedients of welding,drilling, tapping, riveting and the like. Also, the use of rigid corematerial gives the door unusual strength combined with sound deadeningand insulation advantages, plus economy.

While the present invention has been described with reference to thespecific details of certain embodiments, it is not intended that suchdetails shall be regarded as limitations upon the scope of theinvention, except insofar as included in the accompanying claims.

I claim:

1. A panel assembly comprising a unitary panel framing member having anelongated body portion with a longitudinally extending T-shape flangeintegrally formed thereon, said T-shape flange having a first portionextending outwardly of the body portion and a second portion extendingtransversely of the body portion and defining with said body portion apair of longitudinally ex: tending opposed grooves, the inner surfacesof said grooves being disposed inwardly of the outermost edge surface ofsaid body portion, the outer surfaces of said grooves being defined bythe inner surfaces of said second portion of said flange, said secondportion of said T- shape flange having an outer surface portion definingthe outermost edge surface of the completed panel assembly, and a pairof substantially flat panel members each having an edge flange directedtowards one of said grooves and closely received and secured therein byopposed walls thereof, said edge flanges being approximately the samethickness as the distance between opposed walls of said grooves, wherebythe marginal edge of each of said panels is concealed along the edge ofthe panel assembly and the panel edge flanges are locked by the T-shapedflange against movement perpendicular to said panel framing member.

2. A panel assembly comprising a rectangular frame of unitary panelframing members having an elongated body portion with a longitudinallyextending flange integrally formed thereon, said elongated body portionbeing a substantially U-shaped channel having a web and a pair offlanges, said integral flange being T-shaped and extending from said webgenerally outwardly of the edge of said frame in a direction opposite tothat of said pair of flanges of said channel, said T-shaped flangeconsisting of a first portion extending outwardly of the body portionand a second portion extending transversely of the body portion anddefining with said body portion a pair of longitudinally extending,opposed grooves that are spaced from and open towards opposite sides ofsaid frame, said first and second portions of said flange and theportions of the grooves defined thereby being spaced substantially backfrom the flanges of said channel such that said grooves and saidT-shaped flange are located along the central longitudinal portion ofthe edge of said frame, insulating core material disposed within saidframe, a pair of substantially flat panel members disposed on oppositesides of said frame, said pair of panel members each having an edgeflange directed towards one of said grooves and closely received andsecured therein by opposed Walls thereof, said edge flanges beingapproximately the same thickness as the distance between opposed wallsof said grooves whereby the marginal edge of each of said panels isconcealed along the edge of the panel assembly and the panel edgeflanges are locked by the T-shaped flange against movement perpendicularto the edge of said panel framing members, and an ad hesive layerbetween said panel members and said core material bonding said frame,core material and panel members in assembled relation.

References Cited UNITED STATES PATENTS 2,456,049 12/1948 Carrozza 52-731X 2,796,959 6/1957 Toney 52619 3,001,614 9/1961 Shane 526l9 HENRY C.SUTHERLAND, Primary Examiner.

FRANK L. ABBOTI, Examiner.

G. W. HORNADAY, Assistant Examiner.

2. A PANEL ASSEMBLY COMPRISING A RECTANGULAR FRAME OF UNITARY PANELFRAMING MEMBERS HAVING AN ELONGATED BODY PORTION WITH A LONGITUDINALLYEXTENDING FLANGE INTEGRALLY FORMED THEREON, SAID ELONGATED BODY PORTIONBEING A SUBSTANTIALLY U-SHAPED CHANNEL HAVING A WEB AND A PAIR OFFLANGES, SAID INTEGRAL FLANGE BEING T-SHAPED AND EXTENDING FROM SAID WEBGENERALLY OUTWARDLY OF THE EDGE OF SAID FRAME IN A DIRECTION OPPOSITE TOTHAT OF SAID PAIR OF FLANGES OF SAID CHANNEL, SAID T-SHAPED FLANGECONSISTING OF A FIRST PORTION EXTENDING OUTWARDLY OF THE BODY PORTIONAND A SECOND PORTION EXTENDING TRANSVERSELY OF THE BODY PORTION ANDDEFINING WITH SAID BODY PORTION A PAIR OF LONGITUDINALLY EXTENDING,OPPOSED GROOVES THAT ARE SPACED FROM AND OPEN TOWARDS OPPOSITE SIDES OFSAID FRAME, SAID FIRST AND SECOND PORTIONS OF SAID FLANGE AND THEPORTIONS OF THE GROOVES DEFINED THEREBY BEING SPACED SUBSTANTIALLY BACKFROM THE FLANGES OF SAID CHANNEL SUCH THAT SAID GROOVES AND SAIDT-SHAPED FLANGE ARE LOCATED ALONG THE CENTRAL LONGITUDINAL PORTION OFTHE EDGE OF SAID FRAME, INSULATING CORE MATERIAL DISPOSED WITHIN SAIDFRAME, A PAIR OF SUBSTANTIALLY FLAT PANEL MEMBERS DISPOSED ON OPPOSITESIDES OF SAID FRAME, SAID PAIR OF PANEL MEMBERS EACH HAVING AN EDGEFLANGE DIRECTED TOWARDS ONE OF SAID GROOVES AND CLOSELY RECEIVED ANDSECURED THEREIN BY OPPOSED WALLS THEREOF, SAID EDGE FLANGES BEINGAPPROXIMATELY THE SAME THICKNESS AS THE DISTANCE BETWEEN OPPOSED WALLSOF SAID GROOVES WHEREBY THE MARGINAL EDGE OF EACH OF SAID PANELS ISCONCEALED ALONG THE EDGE OF THE PANEL ASSEMBLY AND THE PANEL EDGEFLANGES ARE LOCKED BY THE T-SHAPED FLANGE AGAINST MOVEMENT PERPENDICULARTO THE EDGE OF SAID PANEL FRAMING MEMBERS, AND AN ADHESIVE LAYER BETWEENSAID PANEL MEMBERS AND SAID CORE MATERIAL BONDING SAID FRAME, COREMATERIAL AND PANEL MEMBERS IN ASSEMBLED RELATION.